Only update jobs with a later queued_at timestamp#3
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nyergler
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May 14, 2026
Enqueue and PromoteJob have both used ZADD XX GT since #3 to preserve the deferral guarantee for jobs enqueued with deterministic IDs: once a schedule sits at time T in the future, a duplicate enqueue at T' < T must be a no-op, and PromoteJob must not demote a job whose score has been bumped to now + InvisibleSec by Dequeue. That is the right semantic for dedup-style jobs that may race their own re-enqueue. It is the wrong semantic for two cases that have grown up around the queue since: 1. Worker retry rescheduling. When a handler returns an error the retry middleware computes a backoff delay and calls Enqueue with score = now + delay. With GT, that score is rejected because the Dequeue invisibility mark (now + InvisibleSec, typically 60s) is greater. The configured Backoff is effectively dead for any value less than InvisibleSec; gated handlers re-run only on the InvisibleSec cadence regardless of how short the backoff is. 2. Subqueue PromoteOnAck. The subqueue middleware advances the next gated job after the prior handler Acks by calling PromoteJob on that job's ID. With GT, the score (still sitting at the InvisibleSec mark from its last dequeue/gated cycle) is also rejected and the next job continues to wait out its full invisibility window. Add a per-job AllowPromotion flag. Default false preserves today's GT semantics so dedup-deferral jobs are unaffected; setting true causes Enqueue to use plain ZADD XX so backoff can lower the score, and causes PromoteJob to use ZADD XX (without GT) so the next gated subqueue entry can be advanced. The flag is read only after the job is initially enqueued. The Enqueue Lua script splits the per-job arg list into two ZADD calls (one with gt, one without) so a mixed BulkEnqueue stays atomic. PromoteJob does an HGET to read the flag before issuing the ZADD; this adds one round-trip per promotion but keeps the API stable.
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